On Fri, Nov 13, 2020 at 12:52:32 -0600, Ryan Gahagan wrote:
Related issue:
https://gitlab.com/libvirt/libvirt/-/issues/16
Added in support for the following parameters in attach-disk:
--source-protocol
--source-host-name
--source-host-socket
--source-host-transport
Added documentation to virsh.rst specifying usage.
Signed-off-by: Ryan Gahagan <rgahagan(a)cs.utexas.edu>
---
docs/manpages/virsh.rst | 26 ++++++++++---
tools/virsh-domain.c | 85 ++++++++++++++++++++++++++++++++++++++---
2 files changed, 100 insertions(+), 11 deletions(-)
diff --git a/docs/manpages/virsh.rst b/docs/manpages/virsh.rst
index bfd26e3120..a4d70e9211 100644
--- a/docs/manpages/virsh.rst
+++ b/docs/manpages/virsh.rst
@@ -4500,14 +4500,18 @@ attach-disk
[--current]] | [--persistent]] [--targetbus bus]
[--driver driver] [--subdriver subdriver] [--iothread iothread]
[--cache cache] [--io io] [--type type] [--alias alias]
- [--mode mode] [--sourcetype sourcetype] [--serial serial]
- [--wwn wwn] [--rawio] [--address address] [--multifunction]
- [--print-xml]
+ [--mode mode] [--sourcetype sourcetype]
+ [--source-protocol protocol] [--source-host-name hostname:port]
+ [--source-host-transport transport] [--source-host-socket socket]
+ [--serial serial] [--wwn wwn] [--rawio] [--address address]
+ [--multifunction] [--print-xml]
Attach a new disk device to the domain.
-*source* is path for the files and devices. *target* controls the bus or
-device under which the disk is exposed to the guest OS. It indicates the
-"logical" device name; the optional *targetbus* attribute specifies the type
+*source* is path for the files and devices unless *--source-protocol*
+is specified, in which case *source* is the name of a network disk.
+*target* controls the bus or device under which the disk is exposed
+to the guest OS. It indicates the "logical" device name;
+the optional *targetbus* attribute specifies the type
of disk device to emulate; possible values are driver specific, with typical
values being *ide*, *scsi*, *virtio*, *xen*, *usb*, *sata*, or *sd*, if
omitted, the bus type is inferred from the style of the device name (e.g. a
@@ -4541,6 +4545,16 @@ ccw:cssid.ssid.devno. Virtio-ccw devices must have their cssid set
to 0xfe.
*multifunction* indicates specified pci address is a multifunction pci device
address.
+There is also support for using a network disk. As specified, the user can
+provide a *--source-protocol* in which case the *source* parameter will
+be interpreted as the source name. *--source-protocol* must be provided
+if the user also wishes to provide host information.
+Host information can be provided using any of the tags
+*--source-host-name*, *--source-host-transport*, and *--source-host-socket*,
+which respectively denote the name of the host, the host's transport method,
+and the socket that the host uses. The *--source-host-name* parameter
+supports host:port syntax if the user wants to provide a port as well.
+
If *--print-xml* is specified, then the XML of the disk that would be attached
is printed instead.
diff --git a/tools/virsh-domain.c b/tools/virsh-domain.c
index 12b35c037d..4c43da7a2c 100644
--- a/tools/virsh-domain.c
+++ b/tools/virsh-domain.c
@@ -222,7 +222,7 @@ static const vshCmdOptDef opts_attach_disk[] = {
{.name = "source",
.type = VSH_OT_DATA,
.flags = VSH_OFLAG_REQ | VSH_OFLAG_EMPTY_OK,
- .help = N_("source of disk device")
+ .help = N_("source of disk device or name of network disk")
},
{.name = "target",
.type = VSH_OT_DATA,
@@ -298,6 +298,22 @@ static const vshCmdOptDef opts_attach_disk[] = {
.type = VSH_OT_BOOL,
.help = N_("print XML document rather than attach the disk")
},
+ {.name = "source-protocol",
+ .type = VSH_OT_STRING,
+ .help = N_("protocol used by disk device source")
+ },
+ {.name = "source-host-name",
+ .type = VSH_OT_STRING,
+ .help = N_("host name for source of disk device")
+ },
+ {.name = "source-host-transport",
+ .type = VSH_OT_STRING,
+ .help = N_("host transport for source of disk device")
+ },
+ {.name = "source-host-socket",
+ .type = VSH_OT_STRING,
+ .help = N_("host socket for source of disk device")
+ },
VIRSH_COMMON_OPT_DOMAIN_PERSISTENT,
VIRSH_COMMON_OPT_DOMAIN_CONFIG,
VIRSH_COMMON_OPT_DOMAIN_LIVE,
@@ -567,6 +583,12 @@ cmdAttachDisk(vshControl *ctl, const vshCmd *cmd)
*iothread = NULL, *cache = NULL, *io = NULL,
*serial = NULL, *straddr = NULL, *wwn = NULL,
*targetbus = NULL, *alias = NULL;
+ const char *source_protocol = NULL;
+ const char *host_name = NULL;
+ const char *host_transport = NULL;
+ const char *host_socket = NULL;
+ char *host_name_copy = NULL;
+ char *host_port = NULL;
struct DiskAddress diskAddr;
bool isFile = false, functionReturn = false;
int ret;
@@ -604,7 +626,11 @@ cmdAttachDisk(vshControl *ctl, const vshCmd *cmd)
vshCommandOptStringReq(ctl, cmd, "address", &straddr) < 0 ||
vshCommandOptStringReq(ctl, cmd, "targetbus", &targetbus) < 0
||
vshCommandOptStringReq(ctl, cmd, "alias", &alias) < 0 ||
- vshCommandOptStringReq(ctl, cmd, "sourcetype", &stype) < 0)
+ vshCommandOptStringReq(ctl, cmd, "sourcetype", &stype) < 0 ||
+ vshCommandOptStringReq(ctl, cmd, "source-protocol",
&source_protocol) < 0 ||
+ vshCommandOptStringReq(ctl, cmd, "source-host-name", &host_name)
< 0 ||
+ vshCommandOptStringReq(ctl, cmd, "source-host-transport",
&host_transport) < 0 ||
+ vshCommandOptStringReq(ctl, cmd, "source-host-socket",
&host_socket) < 0)
goto cleanup;
if (!stype) {
@@ -632,6 +658,13 @@ cmdAttachDisk(vshControl *ctl, const vshCmd *cmd)
if (wwn && !virValidateWWN(wwn))
goto cleanup;
+ if (!source_protocol && (host_name || host_socket || host_transport)) {
+ /* Error: cannot use network host without a source protocol */
+ vshError(ctl, "%s",
+ _("Cannot use --source-host-* parameters without a
--source-protocol"));
+ goto cleanup;
+ }
This can be replaced by:
VSH_REQUIRE_OPTION("source-host-name", "source-protocol");
VSH_REQUIRE_OPTION("source-host-transport", "source-protocol");
VSH_REQUIRE_OPTION("source-host-socket", "source-protocol");
You probably also want:
VSH_EXCLUSIVE_OPTIONS("source-host-name", "source-host-socket")
and also
VSH_REQUIRE_OPTION("source-host-socket", "source-host-transport")
as TCP is assumed by default and it wouldn't work with unix socket path.
+
/* Make XML of disk */
virBufferAsprintf(&buf, "<disk type='%s'",
isFile ? "file" : "block");
I didn't notice this previously. You obviously need "<disk
type='network'"
if defining a network disk.
@@ -659,9 +692,51 @@ cmdAttachDisk(vshControl *ctl, const vshCmd
*cmd)
virBufferAddLit(&buf, "/>\n");
}
- if (source)
- virBufferAsprintf(&buf, "<source %s='%s'/>\n",
- isFile ? "file" : "dev", source);
+ if (source || source_protocol) {
+ virBufferAddLit(&buf, "<source");
+ if (source_protocol) {
+ /* Using a network disk; source is --source-name */
+ virBufferAsprintf(&buf, " protocol='%s'",
source_protocol);
+ if (source)
+ virBufferAsprintf(&buf, " name='%s'", source);
+
+ if (host_name || host_socket || host_transport) {
+ /* Host information provided, add a <host> tag */
+ virBufferAddLit(&buf, ">\n");
+ virBufferAdjustIndent(&buf, 2);
+ virBufferAddLit(&buf, "<host");
+
+ if (host_name) {
+ /* Logic for host:port syntax */
+ host_name_copy = g_strdup(host_name);
host_name_copy variable is not freed, so the string is leaked. Since you
use the variable only in this scope, you can declare it here and also
use 'g_autofree' to free it on scope exit.
+ host_port = strchr(host_name_copy,
':');
+
+ if (host_port) {
+ host_name_copy[(int)(host_port - host_name_copy)] =
'\0';
So this pointer arithmetic expression is a bit pointless:
'ptr[X]' can be written as:
*(ptr + X)
Since strchr() returns 'ptr2 = ptr + n' and you calculate X as 'X = ptr2
- ptr'
Your calculation thus does:
*(ptr + (ptr2 - ptr)) -> *ptr2
You can thus clear the ':' char by:
*host_port = '\0';
Additionally you forgot to move the 'host_port' pointer one after the
colon symbol which is now a NUL byte. That means that host_port actually
looks like an empty string ...
+ virBufferAsprintf(&buf,
+ " name='%s'
port='%s'",
+ host_name_copy, host_port);
And thus this prints just:
$ ./build/libvirt/gcc/tools/virsh attach-disk upstream-bj /tmp/ble vda --source-host-name
test:1234 --source-protocol test --print-xml
<disk type='file'>
<source protocol='test' name='/tmp/ble'>
<host name='test' port=''/>
</source>
<target dev='vda'/>
</disk>
In the above you can actually also see that <disk type='file'> is wrong
as mentioned above.
+ } else {
+ virBufferAsprintf(&buf, " name='%s'",
host_name);
+ }
+ }
+
+ if (host_transport)
+ virBufferAsprintf(&buf, " transport='%s'",
host_transport);
+ if (host_socket)
+ virBufferAsprintf(&buf, " socket='%s'",
host_socket);
+ virBufferAddLit(&buf, "/>\n");
+ virBufferAdjustIndent(&buf, -2);
+ virBufferAddLit(&buf, "</source>\n");
+ }
+ } else {
+ /* Using a local disk; source is file or dev */
+ virBufferAsprintf(&buf, " %s='%s'",
+ isFile ? "file" : "dev", source);
This is still misaligned.
+ virBufferAddLit(&buf, "/>\n");
+ }
+ }
+
virBufferAsprintf(&buf, "<target dev='%s'", target);
if (targetbus)
virBufferAsprintf(&buf, " bus='%s'", targetbus);
Unfortunately this function is very old and would need to be refactored,
the XML formatting is definitely not to our modern standards.